If we (Mexico) still had our land, then we wouldn't have any problems with illegal immigration but now its like ICE is deporting Mexicans from one side of the country to another side of the country and not just from one country to another as it is the "case". It's just like deporting a person from Oklahoma to Kansas and besides, Americans already acquired Oregon country so they already have access to both seas, so invading Mexico would have been futile or pointless. Unless, the U.S. did invade Mexico out of selfishness and greed, stealing land that it doesn't deserve. Maybe with all of the resources in Mexico's former territory, then maybe those resources would have even helped Mexico become a developed nation.
I think the Mexican American war caused many in America to view Mexico as the enemy and this feeling has persisted ever since. It is a form of racism that has its roots less in race than in national sentiment. Now more than 150 years later, people still view Mexico and Mexicans with animosity.
I do not believe the Mexican-American War of 1846-48 is directly responsible for immigration problems with Mexico today. These problems come from the fact that Mexicans want to escape their country and they believe they can live a better life in the United States. When all they have to do is walk across the border, then you create the problem we currently have.
The conditions in Mexico have a great deal to do with what's going on today,not the war that happened 150 years ago. I doubt anyone even knows what that war was about and how it ended. The only thing Americans know is the Alamo,but that still has no bearing on the present.
I doubt very much that the 1846 - 1848 Mexican American war is what's causing the problems with Mexico today. Their primary issues started in the latter half of the 20th century. Their major political party became stagnant and corrupt. They nationalized banks for a time, which caused a national economic depression. And they don't have checks on their police, which leads people to flee corrupt law enforcement when they're in league with the drug cartels.
The cause of the immigration problems today is that our borders a very weak and we have done little to nothing about strengthening our borders to handle the future problems. If we were to strengthen our borders it would be easier to except people who go through legal channels to get to our country.